Cutter-head.



L. F. HESS.

CUTTBR HEAD.

APPLICATION FILED NOV. 9, 1912.

1,109,988. at nted Sept. 8, 1914.

Witnesses lnventgr;

by I I Attorneys TH'E NORRIS PETERS (30., PHOTD-LITHQ. WASHINGTON. D.c.-

UNITED STATES PATENT onnion.

LOUIS F. or ANSTED, wa -T VIRGINIA, ASSIGNGR To Truss nUsTLnss MININGnacnrnn oor/rranv, or Ans'rnn, WEST VIRGINIA.

Specification of Letters Patent.

CUTTER-HEAD.

Patented Sept. 8, 1914:.

Application filed November 9, 1912. Serial No. 730,480.

To all whom it may concern:

Be it known that 1, Louis F. Hess, a citi- Zen of the United States,residing at Ansted, in the county of Fayette and State of Vest V "ginia,have invented a new and useful Cutter-Head, of which the following is aspecification.

One object of the present invention 1s to provide a cutter head for amining machine, having a spiral rib, the rear face of wh ch is soconstructed as to afford an increased amount of space for the cuttings,thereby preventing the cuttings from being ground to powder as they areretracted by the spiral rib.

Another object of the invention is to provide a cutter head for a miningmachine, having a spiral rib so constructed that a minimum amount of thepower employed in driving the head, will be consumed in the operation ofretracting the cuttings.

With the above and other objects in view which will appear as thedescription procoeds, the invention resides in the combina tion andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it being understood that changes in the preciseembodiment of invention herein disclosed can be made within the scope ofwhat is claimed without departing from the spirit of the invention.

In the drawing, Figure 1 shows the invention in side elevation, partsbeing sectioned, and Fig. 2 is an enlarged sectional detail in alongitudinal plane.

In carrying out the invention there is provided a tapered cutter head 1provided with a spiral rib 2, the rib 2 comprising a front face 3 and arear face The front face 3 is disposed at an acute angle to the axis ofthe cutter head, and slants forwardly, the rear face 4 being disposed atan acute angle to the axis of the cutter head and slanting rearwardly.The faces 3 and 4 define an obtuse angle with respect to each other.Inserted into the front face 3 of the spiral rib 2 are cutting tools 5,and a bit 6 is carried by the forward end 7 of the head 1. As indicatedat 8, the rear face 4L of the spiral rib 2 is concaved toward the axisof the cutter head. The concaved rear face 4t of the rib 2 slants fromthe outer edge 9 of one convolution 10 of the front face 3 to the inneredge 11 of an adjoining convolution 12 of the front face 3. Further, the

concaved face 4t is curved away from aline 1l1 lconnecting the points 9and l1,-as clearly shown in Fig. 2. Further, it is to be noted that thedistance between the points 9 and 11, in one convolution of the rearface at, is greater than the distance between the points 9 and 11 of thenext forward convolution of the rear face 4:, so that, in sub stance,the rear face 4 tapers circumferentially of the head, toward the forwardend 7 of the head.

it is to be observed that when the cuttings are retracted by the spiralrib 2, the cuttings, as they move rearwardly, are permitted to expandtransversely of the axis of the cutter head, owing to the concavity ofthe rear face 4:, as indicated at 8. This fea:

ture will be clearly understood when the space which in Fig. 2, existsbetween face 8 and the line 1414- is noted. Owing to the fact that thecuttings, as they are retracted, are permitted to expand transversely ofthe axis of the cutter head, and are not bound between the rear face 1:and the wall of the hole, a minimum amount of the power which isemployed for the rotation of the cutter head is extended in the actualoperation of retracting the cuttings.

It has been pointed out hereinbefore that the distance between thepoints 9 and 11 of one convolution of the face 4 is greater than thedistance between the points 9" and 11 of a forward convolution of theface 4., the face 4 being of greatest Width adjacent the butt of thehead, and tapering, circumferentially of the head, toward the forwardend 7 of the head. Consequently, the cuttings, as they are retracted,are not packed together longitudinally of the axis.

From all of the foregoing it will be obvious that the cuttings, whilethey are being retracted, are not compacted either transversely of theaxis or longitudinally of the axis of the head, the result being that aminimum amount of the power used in rotating the head, goes to effectthe retraction of the cuttings. Further, the cuttings are notcomminuted, and the cutter head herein disclosed will be practicallydustless in operation.

Having thus described the invention what is claimed is 1. A cutter headfor a mining machine, having a spiral rib comprising front and rearfaces, the rear face slanting from the outer edge oi? one eoivrolutionof the front face tmvard the inner edge of an adjoining convolution oithe front face, the rear face being concaved toward the axis of thehead.

2. A cutter head for amining machine, having a spiral rib comprisingfront and rear faces, the rear face being concaved toward the axis ofthe head and away from a line joining the outer edge of one convolutionof the tront face with the inner edge of an adjoining convolution of thefront face.

2). A critter head for a mining machine, inning a spiral rib the rearface 01'? which i3 concaved toward the axis of the head and is taperedoircmnferentiaily of the head toward the forward end of the head.

LOUIS F. HESS.

Witnesses J. N. -Wnieirr, W. C. Morin.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Eatents,

"Washington, G.

